In the original PIIFD [1]}, at first, each feature point is given a main orientation (0 \(\sim \pi \) ), by calculating the local second-order gradient, which ensures rotation invariance. Then the neighborhood of each feature point, the size of which is fixed at \(40*40\)  pixels, is used for description. Taking the main orientation as the datum (0\(^{\circ }\) ), the gradient within the neighborhood is counted. Finally, a descriptor vector of length 128 is generated for feature point description. However, for multi-source remote sensing images with different scales, the information in the local neighborhood can have a large difference, which will lead to different descriptors of the same point.
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